1. Technical Field
The invention relates to a method and an integrated routing device for controlling remote systems via short messages and, in particular, to a method and an integrated routing device that performs verification and manages control durations.
2. Related Art
The appearance of mobile communications technology not only breaks the limitation of conventional fixed, wired communications, but also promotes the applications of various mobile communication devices. In addition to pure voice communication, current mobile communications further enable different mobile communications users to transmit real-time messages in the formats of text, pictures, audio, and videos via short message service (SMS). The users can also obtain news, financial reports, advertisements, and so on, through specific information distribution servers. At the same time, different mobile service provider also provide various mobile services so that people can enjoy a more convenient communication environment.
In the field of auto-control industry, using short messages for remote controls has become a mature technique. It mainly utilizes the wide service range of mobile service and the convenience of message transmissions to send short messages from a sender to a remote system. By this procedure, the input/output (I/O) device at the remote end is controlled by the control end and the data can also be accessed remotely. For example, a mobile communications user away from a factory can control the anti-theft system or various devices via short messages. Typically, the control commands in such short messages have their durations.
SMS has the features of ‘mechanism of storage and transfer’ and ‘mechanism of transmission verification’. The ‘mechanism of storage and transfer’ refers to the mechanism of sending a short message from a sending end to a receiving end via a short message service center (SMSC). Therefore, when the receiving end can only receive low signal or cannot receive any short messages due to storage full, the SMSC temporarily holds the short message and sends it to the receiving end repeatedly until the receiving end receives the short message. The ‘mechanism of transmission verification’ refers to the mechanism that only after the receiving end receives the short message, can the sending end knows that the short message is successfully sent to the receiving end from the SMSC. The sending end, however, does not know how long the short message has been kept at the SMSC.
Based on the above-mentioned two features of SMS, when a short message is used to control a remote system the control command may miss the right time for execution because it is kept at the SMSC for too long. In this case, the remote system (e.g., gate of a reservoir, warning light, siren, etc) may cause serious outcomes because of improper controls. On the other hand, since only users with privileges can send out control commands and such users may send out a series of control commands within a short period of time, the operation load of the remote system may be greatly increased due to overheads in complete verification process for each user, thus negatively affect the performance in remote system. In view of the above-mentioned drawbacks in verification and control duration management, it is necessary to provide a better solution.